What will Happen to Tautara?

                                       

                                                                         Tuatara-burrow

                  ( http://www.victoria.ac.nz/sbs/research/ecology-biodiversity-research/tuatara-biology)

 (Original Diagram)

 It shows the number of male tautara vs female tautara born in the nest depending on temperature. The past temperature (July1999-Feb2001) and current temperature(July2007- Feb2009) is shown and are been compared. At high temperature(76-92°c) we have more male tuatara than female tuatara. At 75 °c we have mixed(male and female) tuatara in the nest.Due to increase in temperaurethere is a high number of male tuatara than female tautara.

              Global warming may therefore skew the sex ratio of tuatara further unless female nest site choice or adaptive shifts in pivotal temperatures compensate for rising temperatures.
  These threats to global biodiversity by climate change is so critical that we need to know the rate at which species respond (Chen et al 2011). Some species can adapt to a warmer temperature by shifting their thermal sensitivity of sex determination (i.e. changing the sex ratio that is based on a specific temperature) or by shifting from temperature dependent sex determination (TSD) to genotypic sex determination (GSD) (which keeps the sex ratio stable). This helps some turtles, amniotes etc to survive but because of the low genetic variation and long generation times of tuatara it doesn't really help tuatara to survive.
  Also, it is expected that climate change might make species ranges shift or even collapse or expand which can lead to a major biodiversity loss (Early & Sax 2011). Therefore, some species uses their behavior to lessen climate warming. This can be done through the shifting of geographical ranges in which species move to high altitudes. Although species like turtle, lizard could shift to high altitudes but tuatara can survive at low altitudes island (Huey and Janzen, 2008)


      Nicola J Mitchell, Michael R Kearney et al explains that tuatara could behaviorally compensate for the male-biasing effects of warmer air temperatures by nesting later in the season or selecting shaded nest sites. But  they realized that at later nesting oviparous species are nesting earlier as climate warms.So due to high temperature, there will be more male tuatara and this can lead to EXTINCTION. (Mitchell and Kearney, 2008)